A gene for grey hair has been identified, potentially paving the way to rejuvenating treatments that can make people look years younger.

The research confirms that greying hair with age is at least partially determined at birth.

Understanding how the IRF4 gene washes colour out of hair might lead to future therapies that halt or reverse the process, scientists believe.

The team also found genes that influence hair curliness and the likelihood of growing a 'monobrow'.

Researcher Dr Kaustubh Ashikari, from University College London, said: "We already know several genes involved in balding and hair colour, but this is the first time a gene for greying had been identified in humans - as well as other genes identifying hair shape and density."

He said the breakthrough was only possible "because we analysed a diverse melting pot of people, which hasn't been done before on this scale".

The team believes the genes are unlikely to work in isolation to cause greying or straight hair, but have a role to play along with other factors yet to be identified.